Two-part adhesives, such as, for example, two-part epoxy adhesives, are used widely, in large doses at construction sites and elsewhere, particularly but not exclusively in order to set studs, anchors, and other hardware into holes bored or otherwise formed within concrete or masonry structure. Such adhesives are commercially available in two-chamber cartridges, which fit into various manually-actuated or pneumatically-actuated dispensers. A commercial source for such adhesives in such cartridges, for such manually-actuated dispensers, and for such pneumatically-actuated dispensers is ITW Ramset/Red Head (a division of Illinois Tool Works Inc.) of Wood Dale, Ill.
Even at a construction site where large doses of such adhesives are used, a single dose may not use the entire contents of such a cartridge, which may contain enough of such adhesive, or of each part of such adhesive, to provide two, three, or more doses. It is known to provide a visible scale, upon an exposed surface of such a cartridge, as a way to measure each dose. When using a manually actuated or pneumatically actuated dispenser, it has been necessary heretofore for the user to visually estimate, as by means of the movement of a rod of the dispenser vis-a-vis such a scale if provided, when each dose has been dispensed. Commonly, moreover, it has been necessary for the user to estimate when a sufficient dose has been injected into a hole.
Consequentally, there has been a need, to which this invention is addressed, for a better way to achieve dosage control with a pneumatically-actuated dispenser for an adhesive, particularly but not exclusively a two-part adhesive, such as, for example, a two-part epoxy adhesive.